vegard_s Posted July 15, 2012 Report Share Posted July 15, 2012 I´m currently trying to teach myself on the timing part of my car. From what I´ve understood this should be 4 ATDC on this CC model with with 2 vacum connections on the distributor. I assume this is an 41202 but I´ve yet to confirm it since I probably need to take it out to see it, it does however say 22D on the top of it. The reason why I´m checking the timing is because I want to rule out any timing issues before I start adjusting the carbs, the spark plugs are as black as they can be. When I started the car and checked the timing it was showing 12 BTDC at 900 idle, the car seems to be running quite fine with this timing. But when I put it on 4 ATDC it really runs crappy, what have I missed? The number 1 seems to be at 5 o clock but I´ve read that is thould be at approx 7 o clock. Any pointers would be great. cheers, Vegard Quote Link to post Share on other sites
poolboy Posted July 15, 2012 Report Share Posted July 15, 2012 (edited) When your engine is idling at around 850 rpms, with the Vacuum Advance and Retard modules disconnected from their vacuum sources on the carbs, your ignition timing should be in the 10 to 14* BTDC range. During the procedure cap the nipple on the top of the front carb that supplied vacuum for the Advance and the nipple on the bottom of the rear carb that supplied Vacuum for the Retard. As far as the orientation of the #1 plug wire, it suggest that when the distributor drive gear was installed engaging the camshaft gear, it should have been rotated about 45 degrees more in a clockwise direction. It may be unsightly to some but no real harm Distributor drive gear on the left, next to the distributor showing it's driven dog. Edited July 15, 2012 by poolboy Quote Link to post Share on other sites
vegard_s Posted July 17, 2012 Author Report Share Posted July 17, 2012 Thanks, but on my setup it seems like there is two identical carbs with vacum on the top on both of them, marked with two blue rings. It does seem to run ok around the 12 BTDC atm. Could anyone shed some light on the thing marked with the red circle on the picture? regards, Vegard Quote Link to post Share on other sites
Guest ntc Posted July 17, 2012 Report Share Posted July 17, 2012 (edited) It's the flame trap? but never seen one like that Edited July 17, 2012 by ntc Quote Link to post Share on other sites
vegard_s Posted July 17, 2012 Author Report Share Posted July 17, 2012 I haven´t seen any references to this on the US 70, Carb version. If anyone could point me to some material regarding this I would be greatful It feels like there has been done some customisation to the original setup. regard, Vegard Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 (edited) Right..a flame trap..Moss part #379-580.You really don't need it but if you keep it, keep it clean inside and unrestricted with emulsified goop. Having the retard vacuum source in that position is in conflict with the vacuum advance. It would appear that the carbs are mis matched for a 70. \ You'll do much better by disconnecting the hose to the retard and capping that nipple on the carb. The retard module is the one on the cockpit side of the distributor. If you want to see how it left the factory before a PO started messing with things: http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32760 http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32761 http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32757 Edited July 17, 2012 by poolboy Quote Link to post Share on other sites
vegard_s Posted July 17, 2012 Author Report Share Posted July 17, 2012 Thanks for the links. It seems like the carbs are mismatch indeed. From what I can see the PO has removed 11,13, 14 and 15 , ref : http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32760 Can you explain it´s purpose and would it be better to remove it and plug it or run without the flame trap? regards, Vegard Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 Seems to me that even Triumph thought it wasn't really necessary, 70 and 71 engines only had that device.. I believe it was designed to prevent a backfire in the carb from reaching the inside of the valve cover.."flame trap". It doesn't do any harm but it must be kept clean inside or else the carbs will not be able to suck thru it and thereby relieve excessive crankcase pressure. All the 70-76 carb'd TR6 engines had a nipple on the valve cover connected to a very low vacuum source on the carbs. There was also a vapor purification chamber called a "carbon cannister", that was where the fuel tank vent terminated. The carbs also sucked on the carbon canister thru a hose "T'd from the valve cover. You don't need the carbon canister, but you do need to keep a connection from the valve cover to at least one carb regardless of whether or not you keep the Flame Trap. Here's my engine stripped of all unnecessary emission plumbing: Quote Link to post Share on other sites
Rien Posted July 17, 2012 Report Share Posted July 17, 2012 Seems to me that even Triumph thought it wasn't really necessary, 70 and 71 engines only had that device.. I believe it was designed to prevent a backfire in the carb from reaching the inside of the valve cover.."flame trap". It doesn't do any harm but it must be kept clean inside or else the carbs will not be able to suck thru it and thereby relieve excessive crankcase pressure. All the 70-76 carb'd TR6 engines had a nipple on the valve cover connected to a very low vacuum source on the carbs. There was also a vapor purification chamber called a "carbon cannister", that was where the fuel tank vent terminated. The carbs also sucked on the carbon canister thru a hose "T'd from the valve cover. You don't need the carbon canister, but you do need to keep a connection from the valve cover to at least one carb regardless of whether or not you keep the Flame Trap. Here's my engine stripped of all unnecessary emission plumbing: Hi Poolboy, Nice heater valve, are they better than the OE? Regards, Rien Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 Thanks Rien. A lot of people say so but I'm not exactly sure why. It's designed for an old American Motors vehicle. Quote Link to post Share on other sites
Guest ntc Posted July 17, 2012 Report Share Posted July 17, 2012 You do need the flame trap Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 No. It was deleted after 1971. Whether or not it was ever needed I can't say, but I haven't heard anything bad happening because it was not installed, whereas if it is allowed to clog up with emulsion, crankcase pressure will build up and blow oil out of various seals and seams. Quote Link to post Share on other sites
Guest ntc Posted July 17, 2012 Report Share Posted July 17, 2012 Back pressure with blow by and incorrect fuel mixture or timing fault and then you would see why it should be fitted Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 Unique to 70 and 71 engines then ? Quote Link to post Share on other sites
Rien Posted July 17, 2012 Report Share Posted July 17, 2012 Unique to 70 and 71 engines then ? No not unique, they all have a breather like Vegard or a crancase emission control valve that act as a flame trap to. Regards, Rien Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 (edited) Nope. A flame trap is a flame trap. You won't find a flame trap inbetween the valve cover and the CARBS after the year of 1971 Edited July 17, 2012 by poolboy Quote Link to post Share on other sites
Guest ntc Posted July 17, 2012 Report Share Posted July 17, 2012 Wanna bet? Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 (edited) I'm game. Show me. Edited July 17, 2012 by poolboy Quote Link to post Share on other sites
Guest ntc Posted July 17, 2012 Report Share Posted July 17, 2012 74 usa car owned by me 12k on the clock years ago I will dig the pics out later Quote Link to post Share on other sites
Rien Posted July 17, 2012 Report Share Posted July 17, 2012 Hi to CC50000 they have a EMC valve that are a flame trap, after that they have the carbon canister and a flame trap between the two T pices that came from the rocker cover. Regards, Rien Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 I had a 74 myself; they did not come with a flame trap Now, anybody can do anything they have a mind to, but it didn't come that way. Have a look at the links I provided in post #6. You take the flame trap out of that section of hose on the 70 & 71 engines and the crankcase pressure relief set up is identical to the following years. Quote Link to post Share on other sites
Guest ntc Posted July 17, 2012 Report Share Posted July 17, 2012 Moss do not get it right sometimes Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 Hi to CC50000 they have a EMC valve that are a flame trap, after that they have the carbon canister and a flame trap between the two T pices that came from the rocker cover. Regards, Rien Any chance you'd care to have a look at this ? http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=32760 If you remove the 70-71 flame trap, the connection from the carbs to the valve cover is identical to the following years... Quote Link to post Share on other sites
poolboy Posted July 17, 2012 Report Share Posted July 17, 2012 (edited) Moss do not get it right sometimes I've had my head under quite a few bonnets. They have it right. If the 72, 73, 74, 75, 76, engines did not need a flame trap in that location, there's no reason to believe vegard-s' engine really does. Keep it if you want, but keep it clean. Edited July 17, 2012 by poolboy Quote Link to post Share on other sites
Rien Posted July 17, 2012 Report Share Posted July 17, 2012 Any chance you'd care to have a look at this ? http://www.mossmotor...teIndexID=32760 If you remove the 70-71 flame trap, the connection from the carbs to the valve cover is identical to the following years... Hi Poolboy,You're exactly right after 1973 he was no longer mounted, I found in the original workshop manual. I'm glad we have injection, much simpler! Rien Quote Link to post Share on other sites
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